A
An access specifier controls the access of nonmember functions to the member functions and variables of a class. The C++ access specifiers are public, private, and protected. See public, private, and protected for details. Also see friend.
Access time is a measure of how long it takes to retrieve data from a storage device, such as a hard disk or RAM.
Address; see memory address.
An algorithm is a set of precisely defined steps guaranteed to arrive at an answer to a problem or set of problems. As this implies, a set of steps that might never end is not an algorithm in the strictest sense.
Aliasing is the practice of referring to one object by more than one “name”; in C++, these names are actually pointers or references.
The aliasing problem is a name for the difficulties that are caused by altering a shared object.
An application program is a program that actually accomplishes some useful or interesting task. Examples include inventory control, payroll, and games.
An application programmer (or class user) is a programmer who uses native and class variables to write an application program. Also see library designer.
An argument is a value supplied by one function (the calling function) that wishes to make use of the services of another function (the called function). There are two main types of arguments: value arguments, which are copies of the values from the calling function, and reference arguments, which are not copies but actually refer to variables in the calling function.
An argument list is a set of argument definitions specified in a function declaration. The argument list describes the types and names of all the variables the function receives when it is called by a calling function.
An array is a group of elements of the same type — for example, an array of chars. The array name corresponds to the address of the first of these elements; the other elements follow the first one immediately in memory. As with a vector, we can refer to the individual elements by their indexes. Thus, if we have an array of chars called m_Data, m_Data[i] refers to the ith char in the array. Also see pointer, vector.
An array initialization list is a list of values used to initialize the elements of an array. The ability to specify a list of values for an array is built into the C++ language and is not available for user-defined data types such as the vector.
The ASCII code is a standardized representation of characters by binary or hexadecimal values. For example, the letter “A” is represented as a char with the hexadecimal value 41, and the digit 0 is represented as a char with the hexadecimal value 30. All other printable characters also have representations in the ASCII code.
An assembler is a program that translates assembly language instructions into machine instructions.
An assembly language instruction is the human-readable representation of a machine instruction.
Assignment is the operation of setting a variable to a value. The operator that indicates assignment is the equal sign, =. Also see operator = in the index.
An assignment operator is a function that sets a preexisting variable to a value of the same type. There are three varieties of assignment operators:
For a variable of a native type, the compiler supplies a native assignment operator.
For a variable of a class type, the compiler generates its own version of an assignment operator (a compiler-generated assignment operator) if the class writer does not write one.
The class writer can write a member function (a user-defined assignment operator) to do the assignment; see operator = in the index.
An assignment statement such as x = 5; is not an algebraic equality, no matter how much it may resemble one. It is a command telling the compiler to assign a value to a variable. In the example, the variable is x and the value is 5.
The auto storage class is the default storage class for variables declared within C++ functions. When we define a variable of the auto storage class, its memory address is assigned automatically upon entry to the function where it is defined; the memory address is valid for the duration of that function.
Automatic conversion is a feature of C++ that allows an expression of one type to be used where another type is expected. For example, a short variable or expression can be provided when an int expression is expected, and the compiler will convert the type of the expression automatically.